Wave compensation on telephone lines



. Receiver Feb. 15, 1927. 1,617,370

G. E. BLIZIOTIS WAVE COMPENSATION 0N TELEPHONE 'LINES Filed Sept. s, 1925 w| ESSES- I INVENTOR X Gqyemm fl/lZ/d/Zi ATTORNEY GEoReEj PAivi' BZIZYJT'EOTISQOF ivnwfli-iinsriir, Assi'Gii oRfT Q wnsriiiisrioiisn j ELEorRro a MANUFACTURINGHCOMPANY, AooRPonATIoii or PnnN'sYLYANIA-. f

' This invention relates to :transmission lines and particularly to lines used for tele- WAVE ooiit-rnnsa'rion on 'rELEPjrronE trues implication. ai aseptemii r s, r9231 serial Na. ee'i s ssm phonic transmission. a v i 7 It is "an object of this invention'to provide means forprotecting telephone instrur ments from the; effects of inductive action by neighboring lines such as electric light in1 and powerlines.

It is'a furthe'r'object of this invention to so arrange telephone transmission lines that the impulses due to the. inductive action of neighboring lines will produce in the receiving' circuit equal and opposite etfests which cancel one another.

These and other objects will be made .ap; parent through; the further description of my inventionwhich is illustrated in. the accompanying drawings, wherein the; single figure illustrates diagrammatically {a vtelephone line, embodying my invention.

In this figure, 14s a source or telephone current. A switch 2 enables the energy from this source to .be impressed upon either of two circuits 3 and 4. These are the' prima ry circuits of a" pair of transformers and .6. The circuit 3 is inductively connected by the transformer 5 to a line circuit 7, which is afcomplete metallic circuit including the secondary coil of the transformer 5, two line'wires and a primary 'coilf 8 at the receiving end of the line. The

primary circuit 4 is inductively connected 13 which supplies the receiving circuit 16.-

The drawing shows in dotted lines a number' of neighboring. wires 14, 15 which are intended to I represent parts of any disturbing lines such as electric lighting lines, high-tension power lines, trolleywires or any other sources'of disturbance that might 'cause noises in the telephone receivers, In

the operation of the device, any inductive are Wound u n the transformer 12 in'such influence emanating from the wires 14 produces current simultaneously in both the'cir-w cuit s 7 and 9. The primary coils Sand 11 relative directions that the flux due to the induced current, in line 7 will oppose the flux due to the current simultaneously-1m ,duced in theline 9. In the'same way wh'en the wires 15 exercise 7 an inductive influence,

the current induced in one .0f the two line circuits 7 and 9 will produce a. flux in the transformer 12 that "opposes that produced by the current in the other of said line circuits; Thus, whether the extraneous influ ence comesfrom the one side ofthe tele phone line system or the otherfthe disturb dominate, .th'is ite'nden cy will, be corrected by such ad ustmenta Thus. the ;electroniot ive forces induced in the: receivingf circuit by extraneous, disturbing influences can; be,

Vance-s set up' in'thetransformer 12 are oppo= if the influence of either one? tends to .fpre

made to cancel one another and no noise will be produced in the telephone instruments because of such disturbances;

The invention is applicable to, any transmission system using telephone lines in pairs,

whetherthese lines are used, simultaneously v for carrying two or more messagesoru'sed singly as illustrated in the drawing. The

single use of thelines has been indicated by providing the switch 2, but it is obvious to those skilled'in the art that any of the standard ways of arranging't-he sending end; of a telephone transmission system may be substituted for the source 1 and the switch 2 7 While I have illustrated but one embodiment of my invention it willbejapparent to those skilled inthe artthat various changes vwithout departing from the spirit and scope of this invention. i

paratus illustrated without departingfrom.

the spirit andsco-pe of my invention, as set forth in the appended claims. "I claim asmy invention:

"ion

1'. transmission system including two. neighboring complete metallic. lines, means 7.

said common receiving circuit ininductivef' opposition to, one another withfrespectto a field resulting from an external. circuit. transmission systemfincluding' two and modifications may be made in the ap-.

neighboring complete metallic lines, means at the sending end for impressing current on at least one ofrsaid lines, a common re- C(31Vlng,-ClICU1t3,' a transformer at the recenn ing endincluding a secondary in said receiving circuit and two primaries one in each of said lines, said primaries being in: duetively opposed to one another with re spectfto a field resulting-from an external circuit.

A telephone system including *two complete metalilc' lmes,' a

neighboring power line ad acent thereto, means at the sending end'for impressing current on at least one ofsaid telephone lines a common receiving circu1t,=n1eans at the receiving end for inductively coupling said telephone lines to each other and to the common re- V sending end toriimpressing current on at least one of said lines, a: common receiving circuit, an1 inductively 'related power line;

-means atithe receiving endifor' inducti vely coupling saidtelephone' lines to each-l other subscribed and, to the commonreceiving circuit, said coupling being so connected that impulses in said lines due to inductive influences ol the power linewill cause opp0smg'electromotive torces in said COHPllIlg, CliCllltfELIKl means foradjustinp; said coupling wh'erehy said (opposite electromotive forces-{may be made equal.

In a transmission phone current; means for impressing energy from said source upon either ot'said lines,"

the other of said lines being thenpdisconnectedrfrom sait Eource,-a receiving 'circuit remote from said. source common to said lines, anrzuljacent power circuit, two primaries one in eacl i-ofsaid tines, said primaries being in inductive relation to each other-and wound to produce fluxes in opposite directions in response to influences act+ ing upon bothof saidlines'from said power circuit, a secondary in saidreceiving circuit 111 inductive reiatlon to both'of said pr].-

maries and means for. independently ra d-V system' two neighbor mg complete metallic lines, a source of tele justing the couplingbetweenreach of said primaries and said secondary."

In testimony whereof; I have'hereunto i GEORGE 'EPAM BLIZI PrIsQ my namev this QOthsdey of Augz, 

